1. Field of the Invention
This invention relates to a waste water treating process scheme including anaerobic and aerobic biological treatments.
2. Description of Information Disclosures
Process schemes for treatment of waste water are known.
U.S. Pat. No. 4,487,697 discloses treating waste water using a mechanical clarifier, an anaerobic treatment and an aerobic treatment.
U.S. Pat. No. 4,315,823 discloses treating waste water in an anaerobic filter to which an alkaline material is added followed by aerobic treatment.
U.S. Pat. No. 4,522,722 discloses anaerobic treatment and aerobic treatment of waste water.
U.S. Pat. Nos. 4,137,168; 4,290,884; and 4,384,956 disclose anaerobic and aerobic treatment of waste water.
It has been disclosed that sodium inhibits anaerobic microorganisms. See, for example, McCarthy and McKinney "Volatile Acid Toxicity in Anaerobic Digestion", Journal of Water Pollution Control, Fed. Vol. 33, No. 3, pages 223-232.
It has now been found that waste water comprising insoluble oil and solids, soluble organic pollutants, H.sub.2 S and salts of alkali metals and Group II A metals, such as water separated from crude oil at a production well, may be treated to meet environmentally acceptable requirements by a specific sequence of processing steps including an anaerobic treatment.